
Lake Hévíz
lake · KeszthelyLake Hévíz, in the town of Hévíz near Keszthely, is the largest swimmable natural thermal lake in Europe. Its water rises from two springs in a 38-metre cave and is fully replaced roughly every three and a half days, keeping the lake between 33-35°C in summer and around 22°C in winter. Water lilies, introduced in 1898, now cover much of its surface.